Like comparing a horse and a plane. Classical computers are better at some tasks than quantum computers (email, spreadsheets and desktop publishing to name a few). The intent of quantum computers is to be a different tool to solve different problems, not to replace classical computers.

Google announced it has a quantum computer that is 100 million times faster than any classical computer in its lab.

Every day, we produce 2.5 exabytes of data. That number is equivalent to the content on 5 million laptops. Quantum computers will make it possible to process the amount of data we’re generating in the age of big data.

According to Professor Catherine McGeoch at Amherst University, a quantum computer is “thousands of times” faster than a conventional computer.

Superposition is the term used to describe the quantum state where particles can exist in multiple states at the same time, and which allows quantum computers to look at many different variables at the same time.

Rather than use more electricity, quantum computers will reduce power consumption anywhere from 100 up to 1000 times because quantum computers use quantum tunnelling.

Quantum computers are very fragile. Any kind of vibration impacts the atoms and causes decoherence. This means that extensive error correction is required.

There are several algorithms already developed for quantum computers including Grover’s for searching an unstructured database and Shor’s for factoring large numbers.

Remember when IBM’s computer Deep Blue defeated chess champion, Garry Kasparov in 1997? It was able to gain a competitive advantage because it examined 200 million possible moves each second. A quantum machine would be able to calculate 1 trillion moves per second!

This year, Google stated publicly that it would produce a viable quantum computer in the next 5 years and added that they would reach “quantum supremacy” with a 50-qubit quantum computer. The top supercomputers can still manage everything a five- to 20-qubit quantum computer can, but will be surpassed by a machine with 50 qubits and will attain supremacy at that point. Shortly after that announcement, IBM said it would offer commercial quantum machines to businesses within a year.